To cope with the increasing demand for wireless data traffic after commercialization of 4G communication systems, active efforts are underway to develop enhanced 5G or pre-5G communication systems. As such, 5G or pre-5G communication systems are referred to as beyond 4G communication systems or post LTE systems. To achieve high data rates, use of the extremely high frequency (mmWave) band (e.g. 60 GHz band) is expected in a 5G communication system. To reduce propagation pathloss and to increase propagation distance at the mmWave band, use of various technologies such as beamforming, massive MIMO, full dimensional MIMO (FD-MIMO), array antenna, analog beamforming and large scale antenna are under discussion for 5G communication systems. To enhance system networks, various technologies such as evolved or advanced small cell, cloud radio access network (cloud RAN), ultra-dense network, device-to-device (D2D) communication, wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP) and interference cancellation are under development for 5G communication systems. In addition, for 5G communication systems, hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC) are under development for advanced coding modulation (ACM), and filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA) are under development for advanced access.
Meanwhile, the Internet is evolving from a human centered network where humans create and consume information into the Internet of Things (IoT) where distributed elements or things process and exchange information. Big data processing through cloud servers and IoT technology are being combined into the Internet of Everything (IoE). To realize IoT services, base technologies such as sensing, wired/wireless communication and network infrastructure, service interfacing and security are needed, and technologies interconnecting things such as sensor networks, Machine-to-Machine (M2M) or Machine Type Communication (MTC) are under development. In IoT environments, it is possible to provide intelligent Internet technology services, which collect and analyze data created by interconnected things to add new values to human life. Through convergence and combination between existing information technologies and various field technologies, IoT technology may be applied to various areas such as smart homes, smart buildings, smart cities, smart or connected cars, smart grids, health-care, smart consumer electronics, and advanced medical services.
Accordingly, various attempts are being made to apply 5G communication systems to IoT networks. For example, sensor networks and machine-to-machine or machine type communication are being realized by use of 5G communication technologies including beamforming, MIMO and array antennas. Application of cloud RANs to big data processing described above may be an instance of convergence of 5G communication technology and IoT technology.
An augmented reality (AR) service may refer to a service that blends real-world images and virtual images together to enable real-time interaction in a three-dimensional context.
Currently, three approaches are mainly used for research on AR services: sensor-based AR, vision-based AR, and hybrid AR.
First, in sensor-based AR, the current location is directly estimated using sensors such as a GPS receiver, gyro sensor, and acceleration sensor, and a location-based AR service may be provided accordingly. Sensor-based AR may make it easy to develop and implement a service through direct use of sensors. However, sensor-based AR service may be not suitable for indoor environments and may produce an erroneous result.
Second, in vision-based AR, an AR service may be provided by use of computer image recognition. A scene captured by an AR device (e.g. terminal) may be analyzed and recognized to provide AR content suitable for the AR device. Vision-based AR may produce a relatively accurate result, but it may be difficult to develop a service using vision-based AR. In addition, vision-based AR requires extra computing power for image recognition and entails additional latency.
Third, in hybrid AR, it is possible to combine advantages of sensor-based AR with those of vision-based AR. That is, hybrid AR may use both image information and sensor information, where sensors may be used for macro tracking and image recognition may be used for more accurate estimation. Hybrid AR attracts attention for much research in recent years, and it may be relatively difficult to develop a service using hybrid AR.
Meanwhile, to realize an AR service, it is necessary for the server to provide AR contents to an AR device with suitable interaction between the AR device and the server.